This invention relates to power converters, and more particularly, to a series capacitor inverter-converter.
This type of converter utilizes an internal series resonant circuit which link a source of AC or DC energy with one or more loads simultaneously. The above cited type of converter is described in detail in the literature and in my U.S. Pat. Nos. 3,953,779 and 4,096,557 issued on Apr. 27, 1976 and June 20, 1978, respectively.
One of the problem areas which arises with the use of this type of converters is the fact that the individual output voltages of the plurality of output terminal pairs depend on the time varying impedances of the loads. Accordingly, the power distribution to the plural loads may vary due to the time varying impedance of a load. The respective voltages across the loads will change whenever the impedance of a load changes and all the other loads that are connected to the single converter will change power consumption accordingly. This problem will occur even if the voltage of one of the loads is stabilized. The voltage of the loads in the impedance has undergone a change, will then vary, causing changes in other load voltages.
This behavior is due to the fact that the loads are driven by a source of electrical energy from the converter rather than a voltage source. In the case of parallel inverters each of the loads is connected to a voltage source. The advantages that have been set forth in the above referred to literature have made the use of the power converter, which employs series resonant circuits, desirable. A removal of the above described shortcoming appears necessary, in order to make this converter suitable for general use, including the feeding of two or more electric loads with independently controlled voltage or current.